<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<body>
<input type=file name="doc" id="doc" onchange="javascript:setImagePreview();">
<p>
<div id="localImag"><img id="preview" width=-1 height=-1 style="diplay:none" /></div>
</p>
<script>
    function setImagePreview() {
        var docObj=document.getElementById("doc");

        var imgObjPreview=document.getElementById("preview");
        if(docObj.files &&    docObj.files[0]){
            //火狐下，直接设img属性
            imgObjPreview.style.display = 'block';
            imgObjPreview.style.width = '300px';
            imgObjPreview.style.height = '120px';
            //imgObjPreview.src = docObj.files[0].getAsDataURL();


            //火狐7以上版本不能用上面的getAsDataURL()方式获取，需要一下方式
            imgObjPreview.src = window.URL.createObjectURL(docObj.files[0]);


        }else{
            //IE下，使用滤镜
            docObj.select();
            var imgSrc = document.selection.createRange().text;
            var localImagId = document.getElementById("localImag");
            //必须设置初始大小
            localImagId.style.width = "300px";
            localImagId.style.height = "120px";
            //图片异常的捕捉，防止用户修改后缀来伪造图片
            try{
                localImagId.style.filter="progid:DXImageTransform.Microsoft.AlphaImageLoader(sizingMethod=scale)";
                localImagId.filters.item("DXImageTransform.Microsoft.AlphaImageLoader").src = imgSrc;
            }catch(e){
                alert("");
                return false;
            }
            imgObjPreview.style.display = 'none';
            document.selection.empty();
        }
        return true;
    }
</script>
</body>

</html>

<form method="post" action="suo_do.php"  enctype="multipart/form-data">
    <input type="file" name="pic" />
    <input type="submit" value="上传1" />
</form>
<?php

/**
 * Created by PhpStorm.
 * User: Administrator
 * Date: 2019/8/21
 * Time: 10:21
 */
class js实现图片上传预览
{

}

header("content-type:text/html;charset=gbk");
ini_set("date.timezone","Asia/chong");
//判断文件是否为空
if(empty($_FILES)){
    echo"上传文件过大";
    exit;
}
//判断文件上传是否有错误
if($_FILES['pic']['error']){
    echo "上传文件";
    exit;
}
//判断文件类型是否非法获取文件后缀
$allowtype=array("jpg","png","jpeg","gif");
$a=explode('.',$_FILES['pic']['name']);
$index=count($a)-1;
$ex=strtolower($a[$index]);
if(!in_array($ex,$allowtype)){
    echo "上传文件非法";
    exit;
}
$file=date('YmdHis').rand().".".$ex;
$src=$_FILES['pic']['tmp_name'];
$des="upload/".$file;
$rs=move_uploaded_file($src,$des);


//缩略图
//读取已经上传图片
$image=imagecreatefromjpeg($des);
$a=getimagesize($des);
$w=$a[0];
$h=$a[1];
if($w>$h){
    $width=300;
    $height=$width/$w*$h;
}else if($w<$h){
    $height=300;
    $width=$height/$h*$w;
}else{
    $width=300;
    $height=300;
}
//创建空白新图片
$newimage=imagecreatetruecolor($width, $height);
//copy源图片内容 copy新图片
imagecopyresized($newimage, $image, 0,0, 0,0, $width, $height, $w, $h);
$filename="upload/s_".$file;
imagejpeg($newimage,$filename);
?>
<?php
header('content-type:text/html;charset=gbk');
/******************************************************************************

参数说明:
$max_file_size  : 上传文件大小限制, 单位BYTE
$destination_folder : 上传文件路径
$watermark   : 是否附加水印(1为加水印,其他为不加水印);

使用说明:
1. 将PHP.INI文件里面的"extension=php_gd2.dll"一行前面的;号去掉,因为我们要用到GD库;
2. 将extension_dir =改为你的php_gd2.dll所在目录;
 ******************************************************************************/

//上传文件类型列表
$uptypes=array(
    'image/jpg',
    'image/jpeg',
    'image/png',
    'image/pjpeg',
    'image/gif',
    'image/bmp',
    'image/x-png'
);

$max_file_size=2000000;     //上传文件大小限制, 单位BYTE
$destination_folder="uploadimg/"; //上传文件路径
$watermark=1;      //是否附加水印(1为加水印,其他为不加水印);
$watertype=1;      //水印类型(1为文字,2为图片)
$waterposition=1;     //水印位置(1为左下角,2为右下角,3为左上角,4为右上角,5为居中);
$waterstring="这是水印";  //水印字符串
$waterimg="xplore.gif";    //水印图片
$imgpreview=1;      //是否生成预览图(1为生成,其他为不生成);
$imgpreviewsize=1/2;    //缩略图比例
?>
<html>
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=gbk" />
    <title>ZwelL图片上传程序</title>
    <style type="text/css">
        <!--
        body
        {
            font-size: 9pt;
        }
        input
        {
            background-color: #66CCFF;
            border: 1px inset #CCCCCC;
        }
        -->
    </style>
</head>

<body>
<form enctype="multipart/form-data" method="post" name="upform">
    上传文件:
    <input name="upfile" type="file">
    <input type="submit" value="上传"><br>
    允许上传的文件类型为:<?=implode(', ',$uptypes)?>
</form>

<?php
if ($_SERVER['REQUEST_METHOD'] == 'POST')
{
    if (!is_uploaded_file($_FILES["upfile"][tmp_name]))
        //是否存在文件
    {
        echo "图片不存在!";
        exit;
    }

    $file = $_FILES["upfile"];
    if($max_file_size < $file["size"])
        //检查文件大小
    {
        echo "文件太大!";
        exit;
    }

    if(!in_array($file["type"], $uptypes))
        //检查文件类型
    {
        echo "文件类型不符!".$file["type"];
        exit;
    }

    if(!file_exists($destination_folder))
    {
        mkdir($destination_folder);
    }

    $filename=$file["tmp_name"];
    $image_size = getimagesize($filename);
    $pinfo=pathinfo($file["name"]);
    $ftype=$pinfo['extension'];
    $destination = $destination_folder.time().".".$ftype;
    if (file_exists($destination) && $overwrite != true)
    {
        echo "同名文件已经存在了";
        exit;
    }

    if(!move_uploaded_file ($filename, $destination))
    {
        echo "移动文件出错";
        exit;
    }

    $pinfo=pathinfo($destination);
    $fname=$pinfo[basename];
    echo " <font color=red>已经成功上传</font><br>文件名:  <font color=blue>".$destination_folder.$fname."</font><br>";
    echo " 宽度:".$image_size[0];
    echo " 长度:".$image_size[1];
    echo "<br> 大小:".$file["size"]." bytes";

    if($watermark==1)
    {
        $iinfo=getimagesize($destination,$iinfo);
        $nimage=imagecreatetruecolor($image_size[0],$image_size[1]);
        $white=imagecolorallocate($nimage,255,255,255);
        $black=imagecolorallocate($nimage,0,0,0);
        $red=imagecolorallocate($nimage,255,0,0);
        imagefill($nimage,0,0,$white);
        switch ($iinfo[2])
        {
            case 1:
                $simage =imagecreatefromgif($destination);
                break;
            case 2:
                $simage =imagecreatefromjpeg($destination);
                break;
            case 3:
                $simage =imagecreatefrompng($destination);
                break;
            case 6:
                $simage =imagecreatefromwbmp($destination);
                break;
            default:
                die("不支持的文件类型");
                exit;
        }

        imagecopy($nimage,$simage,0,0,0,0,$image_size[0],$image_size[1]);
        imagefilledrectangle($nimage,1,$image_size[1]-15,80,$image_size[1],$white);

        switch($watertype)
        {
            case 1:   //加水印字符串
                imagestring($nimage,2,3,$image_size[1]-15,$waterstring,$black);
                break;
            case 2:   //加水印图片
                $simage1 =imagecreatefromgif("xplore.gif");
                imagecopy($nimage,$simage1,0,0,0,0,85,15);
                imagedestroy($simage1);
                break;
        }

        switch ($iinfo[2])
        {
            case 1:
                //imagegif($nimage, $destination);
                imagejpeg($nimage, $destination);
                break;
            case 2:
                imagejpeg($nimage, $destination);
                break;
            case 3:
                imagepng($nimage, $destination);
                break;
            case 6:
                imagewbmp($nimage, $destination);
                //imagejpeg($nimage, $destination);
                break;
        }

        //覆盖原上传文件
        imagedestroy($nimage);
        imagedestroy($simage);
    }

    if($imgpreview==1)
    {
        echo "<br>图片预览:<br>";
        echo "<img src=\"".$destination."\" width=".($image_size[0]*$imgpreviewsize)." height=".($image_size[1]*$imgpreviewsize);
        echo " alt=\"图片预览:\r文件名:".$destination."\r上传时间:\">";
    }
}
?>
</body>
</html>
